The proposed study will examine the extent to which quality measures used in the HEDIS (Health Plan Employer Data and Information Set) 2000, reflect cost-effective practices. While the number of published cost- effectiveness analyses (CEAs) has increased rapidly, little is known about whether the information is being used and for what purposes. The study takes advantage of a unique new database of 228 cost-utility analyses (CUAs) and 650 standardized cost per QALY (quality adjusted life year) ratios constructed through a comprehensive search of the medical literature through 1997. Focusing on the effectiveness of care measures in HEDIS, the objectives are to 1) determine the extent of cost-effectiveness evidence underlying HEDIS 2000; 2) examine the strength of this evidence; 3) analyze the variation in cost- effectiveness ratios across HEDIS measures; 4) examine quality measures not used in HEDIS for which the cost-effectiveness evidence exists; 5) explore economic evidence from approaches other than CEAs underlying HEDIS; 6) explore the possibility of linking the CEA database to other quality measurement systems. The applicant plans to accomplish these objectives through a systematic linking of the evidence from the already created CEA database to the HEDIS measures, some basic analysis of CEA studies which can be linked to HEDIS measures, and additional searches of the CEA database and other databases to identify other useful information and linkages.